2,17x+4,18=45,12
2,17x=45,12-4,18
2,17x=40,94
x=40,94/2,17
x=18,8(примерно)
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34,12x+67,54-21,16x=408,8
12,96x+67,54=408,8
12,96x=408,8-67,54
12,96x=341,26
x=341,26/12,96
x=26,3(примерно)
5/8*4/15=1/2*1/3=1/6
6 3/4*1 11/45=27/4*56/45=3/1*14/5=42/5=8 2/5